I purchased a Cecilio Electric CEVN-1 from fiddlershop.com after discovering the wealth of online resources and community at fiddlerman.com that's there for someone like me, as an adult learner, who wasn't ready to sign up with an instructor from day one. I also discovered violintutorpro.com shortly after, starting online lessons with Michael Sanchez. Between these two sites and the amazing, supportive communities that have built up around them, along with some great new friends from these communities, I have more than enough inspiration and help for years to come.
I also purchased Smartmusic and I'm sure it's helping me learn faster and it makes it so much more enjoyable hearing myself play to a backing track. The instant score and other feedback (intonation, rhythm, etc) is very helpful and makes me strive to keep getting higher scores, like a video game only better.